The present invention relates generally to the field of coke plants for producing coke from coal. Coke is an important raw material used to make steel. Coke is produced by driving off the volatile fraction of coal, which is typically about 25% of the mass. Hot exhaust gases generated by the coke making process are ideally recaptured and used to generate electricity. One style of coke oven which is suited to recover these hot exhaust gases are Horizontal Heat Recovery (HHR) ovens which have a unique environmental advantage over chemical byproduct ovens based upon the relative operating atmospheric pressure conditions inside the oven. HHR ovens operate under negative pressure whereas chemical byproduct ovens operate at a slightly positive atmospheric pressure. Both oven types are typically constructed of refractory bricks and other materials in which creating a substantially airtight environment can be a challenge because small cracks can form in these structures during day-to-day operation. Chemical byproduct ovens are kept at a positive pressure to avoid oxidizing recoverable products and overheating the ovens. Conversely, HHR ovens are kept at a negative pressure, drawing in air from outside the oven to oxidize the coal volatiles and to release the heat of combustion within the oven. These opposite operating pressure conditions and combustion systems are important design differences between HHR ovens and chemical byproduct ovens. It is important to minimize the loss of volatile gases to the environment so the combination of positive atmospheric conditions and small openings or cracks in chemical byproduct ovens allow raw coke oven gas (“COG”) and hazardous pollutants to leak into the atmosphere. Conversely, the negative atmospheric conditions and small openings or cracks in the HHR ovens or locations elsewhere in the coke plant simply allow additional air to be drawn into the oven or other locations in the coke plant so that the negative atmospheric conditions resist the loss of COG to the atmosphere.